Oracle Archives - ASRblogger

Reinstate or Recreate Standby DB after Failover

Reinstate Previous Primary DB as standby after Failover completed Fast_start failover initiated by Oracle: Oracle will try to reinstate old primary db as new standby. In case of failure (corrupted…

Anish Kumar January 29, 2026No Comments

ORA-00020: maximum number of processes (<limit>) exceeded</limit>

Oracle

ORA-00020: maximum number of processes () exceeded

Check database parameter To check database parameter in general: SQL> show parameter cursors ## list all parameter with name .*cursors.* NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ open_cursors integer 300 session_cached_cursors…

Anish Kumar January 29, 2026No Comments

ASM DataGuard Oracle

Approach for Troubleshooting Oracle Database Unavailability in a Production Environment

Quickstart When an Oracle Database becomes unavailable in a production (PRD) environment, troubleshooting should follow a structured and non-destructive approach to preserve evidence and avoid data loss. 1. Capture the…

Anish Kumar January 29, 2026No Comments

Oracle

Analyzing Oracle Database Performance Issues in Production Environments

Introduction A top-down approach is strongly recommended when analyzing database performance issues. The sequence of topics in this guide should not be interpreted as a fixed starting point; effective troubleshooting…

Anish Kumar January 29, 2026No Comments

Oracle

High Undo Tablespace Space Usage

Introduction UNDO is controlled by undo_retention parameter and size of UNDO tablespace. UNDO_RETENTION: low threshold value (in sec) of undo retention. If an active transaction requires undo space and the…

Anish Kumar January 29, 2026No Comments

DataGuard Oracle RAC

Resizing redo logs and standby Redologs in Dataguard

IN PRIMARY DATABASE :- 1) Check Instance details :- select status,instance_name,database_role from v$database,v$instance; ------------------------------------------------------------------------------------------------------------------------------------ 2) Check redo log and standby redo log size in Primary and standby :- Redo log…

asrblogger March 22, 2025No Comments

DataGuard Oracle

Resync Standby Database Using RMAN Incremental Backups

Normally in DR setup, the archives from primary shipped to standby and applied there. Suppose some of the archives hasn’t been shipped to secondary .But due to intermittence error or…

asrblogger March 21, 2025No Comments

DataGuard Oracle

Step by Step Data Guard Configuration in 19c

1) PREREQUISITES: Requirements before starting the DATA GUARD CONFIGURATION. NOTE: 1) In PRIMARY SERVER DG11 we need to install the BINARIES OF ORACLE 19c and then create only 1 PRIMARY…

asrblogger March 20, 2025No Comments

DataGuard Oracle

Switchover to Physical Standby Database in Oracle !!

Once the standby database is configured and verified to be working properly, we can switch over to the standby database for testing purposes. This helps to minimize downtime for the…

asrblogger March 15, 2025No Comments

DataGuard Oracle

2 node RAC with Dataguard Configuration (DGMGRL)

This guide will take you through the steps configure Oracle Grid Infrastructure 12c and Database 12c including RAC to RAC Data Guard and Data Broker configuration in a Primary and…